Transcript
USOO8811375B2
(12) Unlted States Patent
(10) Patent N0.2
Gha et a]. (54)
(45) Date of Patent:
MULTIMEDIA APPARATUS AND
(75) Inventors: Hwang-hyeon Gha, Suwon-si (KR); Byeong'woon Ha, SUWOH'Si (KR)
370/329, 508, 509, 513, 514, 350; 455/41.2, 411, 6.01, 3.06 see application ?le for complete searCh hiSTOI'Y (56) References Cited
(73) Assignee: Samsung Electronics Co., Ltd.,
Notice:
*Aug. 19, 2014
USPC ....... .. 370/517, 519, 419, 420, 412, 503, 328,
SYNCHRONIZATION METHOD THEREOF
(*)
US 8,811,375 B2
U-S- PATENT DOCUMENTS
SUWOH'SI(KR)
7,088,832 B1
Subject to any disclaimer, the term of this patent is extended or adjusted under 35
7,324,462 B1 1/2008 Page et al. 7,365,766 B1 * 4/2008 Lapalme ....................... .. 348/61 * l 455/3 06
U.S.C.154b
b
( ) y
59d
ays
.
I
I
7,653,344 B1
This patent is subject to a terminal dis-
8,199,780 132*
Claimen
8,325,930 B2 *
8/2006 Cooper
e
011% ~~~~~~~~~~~~~~~~~~~~~~ ~~
1/2010 Feldman et al.
~
6/2012 G113 et al~ ~~~~~~~~~~~~~~~~~~~~ ~~ 370/517 12/2012
Klm et a1. ....................... .. 381/2
(Continued) (21) Appl.No.: 13/471,173 (22) Filed:
FOREIGN PATENT DOCUMENTS
May 14, 2012
(65)
EP EP
1 619 902 A2 1 657 929 A1
Prior Publication Data US 2012/0224100 A1
(Continued)
Sep. 6, 2012
OTHER PUBLICATIONS Communication from the European Patent Of?ce dated Mar. 16, 2010,'m E mopean Applcalon 1' t' N.08153638.5. 0
Related U.S.Application Data
(63) Continuation of application No. 12/138,613, ?led on Jun. 13, 2008, now Pat. NO. 8,199,780.
(30)
1/2006 5/2006
(connnued) Primary Examiner * Hanh N Nguyen (74) Attorney, Agent, or Firm * Sughrue Mion, PLLC
Foreign Application Priority Data
(57)
ABSTRACT
A multimedia apparatus and a synchronization method NOV. 22,
(51)
...................... ..
thereof are provided' The multimedia apparatus includes a
video output unit Which outputs a video, and a control unit Which transmits an audio signal to the external device through
Int. Cl. H04 W 56/00
(2009.01)
the communication module and operates the video output unit to display a video corresponding to the audio signal by delay
(52) us C]_ (58)
USPC ......................... .. 370/350; 370/519; 455/306
1118 the video based on delay information received from the
Field of Classi?cation Search CPC H04W 56/00; H04N 21/4307; H04] 3/0682
external device through the communication module. 10 Claims, 3 Drawing Sheets
I 00
j 10
)20
)30
BROADCAST RECE|V|NG UNlT
A/I/ PROCESSING UNIT
AUDIO OUTPUT UNIT
150\ % STORAGE UNIT
)70
CONTROL UNIT 140
VIDEO OUTPUT UN IT
/160 BLUETOOTH MODULE $
300 HEADSET
US 8,811,375 B2 Page 2 (56)
References Cited U_S_ PATENT DQCUMENTS
KR
1020060068465 A
6/2006
KR
10-2006-0080606 A
7/2006
KR
100651894 B1
12/2006
OTHER PUBLICATIONS 2003/0193616 A1
10/2003
Baker et a1.
_
_
_
2004/0139180 A1 2006/0017846 A1
7/2004 White et al‘ 1/2006 Kim
Communication dated Aug. 17, 2011 issued by the European Patent Of?ce in European Patent Application N0. 081536385.
2006/0140265 A1
6/2006 Igler et 31‘ allele et 31' 1k1 et al.
Colmrsnuiicaltigl dat§%?;;;29, 2011 issued by the US. Patent Of?ce Communincpation dated Jan. 31, 2013 from the European Patent Of?ce -
2007/0211624 A1
9/2007 Schmidt
m founterpm apphcanon-NO' 981642159 - Sa1ram et al., “Bluteooth in Wireless Communication”, IEEE Com
2007/0232222 A1
10/2007 de Jong
munications Magazine, IEEE Service Center, vol. 40, No. 6, Jun. 1,
1n
.
.
.
o.
,
.
2008/0138032 A1*
6/2008 Leyendecker et a1. ........ .. 386/66
2002, pp, 90_96,
2009/0033390 A1 2009/ 009 1655 A1
2/2009 Kim et al~ 4/2009 Russell et a1.
Communication dated Oct. 18, 2013, issued by the Korean Intellec tual Property Of?ce in counterpart Korean Application No. 10-2007
2009/0135856 A1
5/2009 Gha et al.
FOREIGN PATENT DOCUMENTS
0119817.
Communication dated Oct. 17, 2013, issued by the Korean Intellec tual Property Of?ce in counterpart Korean Application No. 10-2007 0077432.
JP
2004282667 A
10/2004
JP
2004-320424 A
11/2004
* cited by examiner
US. Patent
Aug. 19, 2014
Sheet 1 013
US 8,811,375 B2
FIG. 1
jIO BROADCAST
RECHWNG UNIT
120
ISO
A/V PROCESSING UNIT
AUDIOOUTPUT UNIT
'
150\ % STORAGE UNIT
/170
CONTROL UNIT
/160
300
BLUETOOTH MODULE %
HEADSET
I40 /
VI OEO OUTPUT UN IT
FIG. 2
210 INTERFACE UNIT
230 CONTROL UNIT
/250 BUFFER
/270 AUDIO OUTPUT UNIT
US. Patent
l tem
Aug. 19, 2014
Det in i t ion
Service Class l0 List Service Class #0 Protocol Desor iotor List Protocol #0 Parameter #0 for PSM Protocol #0 Protocol #1 Parameter #0 for
Version
Protocol #1 Bluetooth Prof i le Descr iptor List Parameter #0 for
Sheet 2 0f3
Type
Parameter #0 for
Attr l0 Status Detaul t
UU l 0 LZCAP Uni t 16 PSMIAVDTP
M M M M M
Type
M
UU l D
Audio Sink
AVDTP
Uni t 16 0x0100 *
M
M UU l 0
Protocol #0
Protocol #0 Supported Features
Value
US 8,811,375 B2
Advanced Audio
M
Di st r ibut ion
Version
Uni t 16 OXOlOO *‘
M
AZDP features Flags
Uni t 16 Bi t 0:Headphone Bi t lISoeaker Bi t ZIRecorder
0
,Eili?f?llltlilli2L1
tEii_t__£L—_1_5__=__B_F_A__t The bi ts for
supported features are set to l . Others
are set to 0.
Provider Name
Diso l ayable Str ind
Provider Name
0
Text Name
Service Name
Diso l ayable Str ind Service—provider Text Name
det i ned
0
US. Patent
Aug. 19, 2014
Sheet 3 0f3
{—END BIT EDR DELAY TIME
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{—START BIT FOR DELAY TIME
bitIS bit14 --- bItIO UIID bit8 bit7 bit6 bit5 bit4 0
O
---
O
I
O
delSV/TTME
I
0
O
0
delaV UNIT
,S100
/,200
MULTIMEDIA APPARATUS
HEADSET
TRANSMIT AUDIO SIGNAL (S510)
r18520
MEASURE TIME ERDM WHEN mmoaMMIS%%meMM WHEN AUD|0 SIGNAL IS OUTPUT
I
r,8530
GENERATE DELAY INFORMATION BASED ON MEASURED TIME
I SET GENERATED DELAY INFORMATION IN SERVICE RECORD
TRANSMIT SERVICE RECORD (S550) EXTRACT DELAY INFORMATION FROM SERVICE RECORD
S570 DELAY AND OUTPUT VIDEO BASED ON EXTRACTED DELAY INFORMATION
,,S540
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MULTIMEDIA APPARATUS AND SYNCHRONIZATION METHOD THEREOF
audio signals and video signals using delay information acquired from an external device, and a synchronization method thereof.
According to an exemplary aspect of the present invention,
CROSS-REFERENCE TO RELATED APPLICATIONS
there is provided a multimedia apparatus, including a com munication module Which is connected to an external device for Wireless communication, a video output unit Which out puts a video, and a control unit Which transmits an audio
This application is a continuation of Ser. No. 12/138,613 ?led Jun. 13, 2008, and claims priority from Korean Patent Application No. 10-2007-0119817, ?led Nov. 22, 2007 in the Korean Intellectual Property Of?ce, the disclosures of Which are incorporated herein by reference in their entireties.
signal to the external device through the communication module, and operates the video output unit to display a video
corresponding to the audio signal by delaying the video based on delay information received from the external device
through the communication module.
BACKGROUND OF THE INVENTION
The delay information may be contained in a Reserved for Future Addition (RFA) area of the service record received
1. Field of the Invention
from the external device, and the control unit delays the video for a delay time contained in the delay information acquired from the REA area, and then outputs the delayed video to the video output unit.
Apparatuses and methods consistent With the present invention relate to a multimedia device and a synchronization
method thereof, and more particularly, to synchronizing
audio signals and video signals When reproducing images.
20
2. Description of the Related Art
As multimedia technology has developed, multimedia apparatuses for supporting diverse functions using a single device have been introduced. Such multimedia apparatuses
provide not only audio and video recording and playback functions, but also data storage, message transmission, and call functions, such as calling mobile phones. Examples of multimedia apparatuses for recording and reproducing images and broadcast signals received from broadcast sta tions include a digital television (DTV), a portable multime dia player (PMP), a camcorder, a digital camera, a digital video disc (DVD) player, a set-top box (STB), and a mobile
25
The delay information may refer to a data set in the 4th to 15"’ bits of the REA area, and the control unit may calculate the delay time based on the data set in the 4th to 15th bits of the REA area, and delay the video based on the calculated delay time. At least one bit of the 4th to 15th bits of the REA area may be used to set data indicating a delay unit, and the remaining bits except for the at least one bit may be used to set data
indicating the delay time. The service record may be contained in an advanced audio 30
distribution pro?le (A2DP) Which is used in Bluetooth com munication.
The Bluetooth module may acquire the service record by
phone.
Bluetooth communication With the external device using a
service discovery protocol (SDP).
When a related art multimedia apparatus communicates
With a headset using the Bluetooth protocol, the time that video is reproduced is different from the time that audio is
35
According to another exemplary aspect of the present invention, there is provided a synchronization method of a
reproduced by the headset. Speci?cally, since there is a delay
multimedia apparatus, the method including receiving delay
between the time an audio signal is transmitted from the
information by Wireless communication With an external device, and transmitting an audio signal to the external device, and displaying a video corresponding to the audio
multimedia apparatus and the time the signal is output through a speaker of the headset, the audio signal and a corresponding video signal are not synchronized. In particu lar, if a buffer provided by the headset is large, the delay is
40
signal by delaying the video based on the delay information
greater, so the synchronization difference between a video
signal reproduced by the multimedia apparatus and an audio
signal reproduced by the headset increases, causing inconve
45
nience to the user.
Therefore, there is a need for apparatuses and methods for
synchronizing audio signals and video signals When a multi
media apparatus reproduces images. 50
SUMMARY OF THE INVENTION
Exemplary embodiments of the present invention address at least the above problems and/or disadvantages and other disadvantages not described above. Also, the present inven
55
At least one bit of the 4th to 15"’ bits of the REA area may bits except for the at least one bit may be used to set data
indicating the delay time. 60
The service record may be contained in an advanced audio
distribution pro?le (A2DP) using Bluetooth communication.
analyzing a service record acquired using the Bluetooth pro tocol and synchronizing the audio signals and video signals
media apparatus Which is capable of outputting synchronized
calculated delay time. be used to set data indicating a delay unit, and the remaining
signals and video signals by extracting delay information by based on the extracted delay information, and a synchroniza tion method thereof. Another aspect of the present invention provides a multi
and then output. The delay information may refer to data set in the 4th to 15th bits of the REA area, and in the delay operation, the delay time may be calculated based on the data set in the 4th to 15th bits of the REA area, and the video may be delayed based on the
tion is not required to overcome the disadvantages described above, and an exemplary embodiment of the present inven tion may not overcome any of the problems described above. An aspect of the present invention provides a multimedia
apparatus Which is capable of outputting synchronized audio
received from the external device. The Wireless communication may be Bluetooth communi cation, and the delay information may be contained in a service record received from the external device. The delay information may be contained in an RFA area of a packet received from the external device, and in the delay operation, the video may be delayed for a delay time con tained in the delay information acquired from the REA area,
The Wireless communication may be Bluetooth communi
65
cation, and in the receiving operation, the service record may be acquired by Bluetooth communication With the external device using a service discovery protocol (SDP). According to another exemplary aspect of the present invention, there is provided an audio output apparatus,
US 8,8ll,375 B2 3
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including an interface unit which receives an audio signal from an external device, and a control unit which sets delay information based on the period of time taken to output the
With reference to FIG. 1, the multimedia apparatus 100 according to an exemplary embodiment of the present inven tion includes a broadcast receiving unit 110, an audio/video (A/V) processing unit 120, an audio output unit 130, a video output unit 140, a storage unit 150, a Bluetooth module 160,
audio signal. The period of time taken to output the audio signal may indicate a period of time from when the audio signal is received until the audio signal is output, and the control unit may measure the period of time from when the audio signal is received until when the audio signal is output, and set the delay information based on the measured period of time. The control unit may set the delay information, and trans mit the set delay information to the external device through the interface unit. The delay information may include at least one of a delay time and a delay unit.
and a control unit 170.
The broadcast receiving unit 11 0 receives and demodulates a broadcast from a broadcast station or a satellite via a wire
connection or wirelessly. The broadcast receiving unit 110 also receives content from a broadcast station or a satellite.
The content includes moving images, still images, broadcast programs, or audio data.
The A/V processing unit 120 performs video decoding, video scaling or audio decoding of broadcast signals output from the broadcast receiving unit 110. Subsequently, the A/V processing unit 120 transmits video signals to the control unit 170, and audio signals to the audio output unit 130 and the
According to another exemplary aspect of the present invention, there is provided a multimedia apparatus, includ
control unit 170.
ing a communication module which is connected to an exter
nal device for wireless communication, an audio output unit which outputs an audio signal, and a control unit which trans mits a video signal to the external device through the com munication module, and operates the audio output unit to
display an audio signal corresponding to the video signal by delaying the audio signal based on delay information received
20
control unit 170 on a display, or outputs the video to an
external device to which the multimedia apparatus 100 is connected through an external output terminal. 25
The storage unit 150 stores broadcast data processed by the A/V processing unit 120 or programs, software code, instruc tions and the like required to control the elements constituting the multimedia apparatus 100. The Bluetooth module 160 converts audio signals received
30
from the control unit 170 to a format for Bluetooth commu nication, and converts data received from the headset 200 to a
from the external device through the communication module. BRIEF DESCRIPTION OF THE DRAWINGS
The above and/ or other aspects of the present invention will
The audio output unit 130 outputs the audio signals received from the A/V processing unit 120 through a speaker. The video output unit 140 outputs video received from the
be more apparent by describing certain exemplary embodi ments of the present invention with reference to the accom
format capable of being processed by the multimedia appa
panying drawings, in which:
ratus 100.
FIG. 1 is a block diagram of a multimedia apparatus
according to an exemplary embodiment of the present inven
35
extracts delay information from a service record received from the headset 200 using the Bluetooth module 160. The
tion; FIG. 2 is a block diagram of a headset according to an
control unit 170 delays video signals output from the A/V processing unit 120 according to a delay time contained in the
exemplary embodiment of the present invention; FIG. 3 is a drawing illustrating an example of the construc tion of a service record according to an exemplary embodi ment of the present invention; FIG. 4 is a drawing illustrating an example of an RFA area in which delay information is set according to an exemplary
40
embodiment of the present invention; and FIG. 5 is a ?ow chart illustrating a method for synchroniz
The control unit 170 transmits audio signals received from theA/V processing unit 120 to the Bluetooth module 160, and
45
ing audio and video signals between a multimedia apparatus
extracted delay information, and displays the delayed video signals through the video output unit 140. The delay information includes at least one of a delay time and a delay unit, which is a unit of the delayed time. The service record is contained in an advanced audio distribution pro?le (A2DP) which is a pro?le used for transmission and reception of audio data in Bluetooth communication. The
multimedia apparatus 100 performs Bluetooth communica tion with the headset 200 using a service discovery protocol
and a headset according to an exemplary embodiment of the
present invention.
(SDP). DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
50
With reference to FIG. 2, the headset 200 includes an interface unit 210, a control unit 230, a buffer 250, and an
Certain exemplary embodiments of the present invention
audio output unit 270. The headset 200 supports Bluetooth
will now be described in greater detail with reference to the
accompanying drawings.
55
In the following description, like drawing reference numer als are used for like elements, even in different drawings. The matters de?ned in the description, such as detailed construc tion and elements, are provided to assist in a comprehensive
understanding of the invention. However, the present inven
60
tion can be practiced without those speci?cally de?ned mat ters. Also, well-known functions or constructions are not
described in detail since they would obscure the invention with unnecessary detail. FIG. 1 is a block diagram of a multimedia apparatus according to an exemplary embodiment of the present inven tion.
FIG. 2 is a block diagram of a headset according to an
exemplary embodiment of the present invention.
65
communication, and performs wireless communication with the multimedia apparatus 100. The interface unit 210 receives audio signals from the multimedia apparatus 100 using Bluetooth communication. The multimedia apparatus 100 performs Bluetooth commu nication with the headset 200 using an SDP. The control unit 230 buffers the received audio signals using the buffer 250. The control unit 230 measures the time from the time that the audio signals are received until the time that the audio signals are output from the audio output unit 270, and generates delay information based on the measured time. As explained in greater detail below with reference to FIGS. 3 and 4, the control unit 230 contains the delay infor
US 8,811,375 B2 5
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mation in a Reserved for Future Addition (RFA) area con
The control unit 170 of the multimedia apparatus 100 extracts the delay information contained in the received ser
tained in a service record. The delay information includes at least one of a delay time and a delay unit which may include at least one of seconds, milliseconds, microseconds, and nanoseconds.
vice record (S560). Subsequently, the control unit 170 delays and outputs the video signal based on the extracted delay information (S570). For example, if the delay time in the extracted delay infor
More speci?cally, the control unit 230 sets the delay infor mation in bits 4 to 15 of the service record which is predeter
mation is 10 seconds, the control unit 170 delays a video
mined as an RFA as shown in FIG. 3.
signal corresponding to the audio signal transmitted in opera tion S510 for 10 seconds, and then outputs the video signal. Accordingly, the control unit 230 may synchronize the video signal output from the multimedia apparatus 100 with the audio signal output from the headset 200.
For example, if the time from when the audio signals are received until the audio signals are output from the audio output unit 270 is measured at 10 seconds, the control unit 230 sets delay information including a delay time of 10 sec onds and a delay unit “seconds” in the RFA area. More spe
In a multimedia apparatus and a synchronization method
ci?cally, the control unit 230 sets the delay time as “1010”, which is a delay time of 10 converted into binary code, and
thereof according to an exemplary embodiment, the delay information includes a delay time and a delay unit, but the delay information is not limited thereto. In another exemplary embodiment, the delay unit may be predetermined, so that the delay information may include only a delay time. That is, the
sets the delay unit as “00”. As shown in FIG. 4, the control unit 230 uses bits 4 and 5 as the bits for the delay unit, and uses bits 6 to 15 as the bits for
the delay time. That is, the control unit 230 sets the delay time by setting bits 15 to 10, bit 8, and bit 6 to “0” and bits 7 and 9 to “1”. In addition, the control unit 230 sets the delay unit by setting bits 5 and 4 to “0”. The delay unit is set as shown in Table 1. TABLE 1
20
12 bits of the RFA area may be used as the bits for setting the
delay time.
25
In a headset according to an exemplary embodiment of the present invention, a delay unit accounts for 2 bits of the RFA area and a delay time accounts for 10 bits, but the present invention is not limited to such a con?guration. A delay unit may account for 1 bit or more than 2 bits. The remaining bits
Bit5
Bit4
Value
0 0
0 1
1
0
psec (microsecond)
1
1
ns (nanosecond)
except for the bits allocated to the delay unit may be used for
setting the delay time.
sec (second) msec (millisecond) 30
In a headset according to an exemplary embodiment of the present invention, bits 4 and 5 of the RFA area are used to set a delay unit and bits 6 to 15 are used to set a delay time, but the
present invention is not limited to such a con?guration. One
The audio output unit 270 outputs the audio signals from the buffer 250 through a speaker mounted in the headset 200. FIG. 5 is a ?ow chart illustrating a method for synchroniz
or more of bits 4 to 15 may be used to set a delay unit. The
remaining bits other than the bits for setting the delay unit 35
ing audio signals and video signals between a multimedia apparatus and a headset according to an exemplary embodi ment of the present invention. With reference to FIG. 5, the multimedia apparatus 100 transmits to the headset 200 an audio signal corresponding to a video signal to be displayed (S510). The multimedia appa ratus 100 transmits the audio signal to the headset 200 by Bluetooth communication using an SDP protocol. The control unit 230 of the headset 200 measures from the time that the audio signal is received until the time that the
thereof according to an exemplary embodiment of the present invention, the multimedia apparatus transmits data to and receives data from a headset using Bluetooth communication, 40
from the headset by wireless communication. In a multimedia apparatus and a synchronization method
thereof according to an exemplary embodiment of the present 45
multimedia apparatus may acquire the delay information
Subsequently, the control unit 230 of the headset 200 gen erates delay information based on the measured time. The
delay information may include a delay time and a delay unit, which may include at least one of seconds, milliseconds, microseconds, and nanoseconds. In greater detail, the control unit 230 sets the delay time by converting the measured time to binary code, and sets the unit
50
of the measured time as a delay unit.
55
from a packet received from the headset other than the service record. That is, the delay information may be contained in a packet received from the headset other than the service record. In a headset according to an exemplary embodiment of the
present invention, a delay time is calculated by measuring
Subsequently, the control unit 230 sets the generated delay
from the time that an audio signal is received from a multi
media apparatus until the time that the audio signal is output, but it is not limited thereto. The delay time may be calculated as the period of time taken to output the audio signal by the
information in a service record (S540). The service record is contained in anA2DP, which is a pro?le used for transmission 60
delay information in the RFA area contained in the service record, wherein the control unit 230 allocates two bits of the RFA area to a delay unit, and the remaining bits of the RFA
headset. That is, the delay time may refer to the time from when an audio signal is input from one of the elements of the headset until the audio signal is output from another element. In this case, a control unit may calculate the time from when an audio
area to a delay time. The RFA area includes bits 4 to 15.
Bluetooth communication (S550).
invention, the multimedia apparatus acquires delay informa tion from a service record received from a headset, but the present invention is not limited to such a con?guration. The
200 (S520).
The interface unit 210 of the headset 200 transmits the service record to the multimedia apparatus 100 using the
but the communication means is not limited thereto. The
multimedia apparatus may transmit data to and receive data
audio signal is output to the speaker mounted in the headset
and reception of audio data. More speci?cally, the control unit 230 sets the generated
may be used to set a delay time. In a multimedia apparatus and a synchronization method
65
signal is input to a buffer until the audio signal is output from the buffer. That is, the control unit may calculate the delay time by measuring the time during which an audio signal is input to and output from one of the elements of the headset.
US 8,811,375 B2 8
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signal is received until the video signal is output, and sets the delay information based on the measured period of time. 3. The audio output apparatus of claim 1, Wherein the control unit sets the delay information and transmits the set delay information to the external device through the interface unit. 4. The audio output apparatus of claim 1, Wherein the delay
In a multimedia apparatus and a synchronization method
thereof according to an exemplary embodiment of the present
invention, the multimedia apparatus delays an image signal based on delay information of an audio signal, but the present invention is not limited thereto. The multimedia apparatus
may delay an audio signal corresponding to an image signal based on the delay information. The foregoing exemplary embodiments are merely exem plary and are not to be construed as limiting the present
information comprises at least one of a delay time and a delay unit.
invention. The present teaching may be readily applied to other types of apparatuses. Also, the description of the exem plary embodiments of the present invention is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modi?cations, and variations Will be apparent to
5. The audio output apparatus of claim 1, Wherein the delay information is contained in a reserved area of a service record
transmitted to the external device.
6. A method comprising: receiving an audio signal from an external device; determining delay information as a period of time from When a video signal is received by the external device
those skilled in the art.
As may be appreciated from the above description, image signals output from a multimedia apparatus may be synchro nized With audio signals output from a headset by delaying image signals based on delay information extracted from a received service record.
until the video signal is output by the external device; and 20
Audio signals and image signals may be synchronized using delay information acquired from an external device.
audio signal based on the delay information. 7. The method of claim 6, Wherein the determining the
What is claimed is:
1. An audio output apparatus comprising: a communication module Which is communicably linked to an external device for Wireless communication; an audio output unit Which outputs an audio signal; and a control unit Which receives the audio signal from the
delay information comprises: 25
8. The method of claim 6, further comprising transmitting 30
until the video signal is output by the external device, and operates the audio output unit to output the audio signal corresponding to the video signal displayed on the external device by delaying the audio signal based on the
delay information. 2. The audio output apparatus of claim 1 Wherein the con trol unit measures the period of time from When the video
measuring the period of time from When the video signal is received until the video signal is output; and setting the delay information based on the measured period of time.
external device through the communication module, determines delay information as a period of time from When a video signal is received by the external device
outputting the audio signal corresponding to the video signal displayed on the external device by delaying the
the set delay information to the external device through an interface unit.
9. The method of claim 6, Wherein the delay information comprises at least one of a delay time and a delay unit. 35
10. The method of claim 6, Wherein the delay information is contained in a reserved area of a service record transmitted
to the external device. *
*
*
*
*
